Packaging apparatus

ABSTRACT

A METHOD AND APPARATUS FOR PACKAGING ARTICLES SUCH AS CANS IN AN OVERWRAP OF THERMOPLASTIC POLYMERIC MATERIAL IS PROVIDED WHEREIN SAID APPARATUS COMPRISES MEANS FOR GROUPING A PLURALITY OF ARTICLES TO BE PACKAGED, MEANS FOR ENWRAPPING SAID ARTICLES WITH SAID FILM, MEANS FOR HEAT-SEALING OVERLAPPED EDGE PORTIONS OF SAID FILM AND ENCLOSING SAID ARTICLES THEREWITHIN, MEANS FOR SEPARATING SAID FILM-ENWRAPPED GROUPED ARTICLES, AND MEANS FOR SHRINKING SAID HEAT-SEALED FILM TO PROVIDE A PACKAGE OF GROUPED ARTICLES CHARACTERIZED BY A SUBSTANTIALLY WRINKLEFREE FILM EXTENDING OVER THE TOP, BOTTOM, SIDES AND PORTIONS OF THE ENDS OF SAID GROUPED ARTICLES.

Nov. 16, 1971 K. s. CARMICHAEL. 3,619,910

PACKAGING APPARATUS Original Filed July 15, 1968 8 Sheets-Sheet l BY 1} o" SmJ-A ATTORNEY 1971 K. s. CARMICHAEL 3,619,910

PACKAGING APPARATUS Original Filed July 15, 1968 8 Sheets-Sheet 2 BY a WSW ATTOR NE Y NOV. 16, 1971 ARM|CHAEL 3,61Q,910

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ATTORNEY Nov. 16, 1971 K. s. CA'RMICHAEL 3,619,910

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ATTORNEY Nov. 16, 1971 K. s. CARMICHAEL PACKAGING APPARATUS 8 Sheets-Sheet 6 Original Filed July 15, 1968 INVENTOR A/E/TH S-WPM/C/I/IVIFZ7 BY W o" .SW

ATTORNEY Nov. 16, 1971 Original Filed July 15, 1968 K. S. CARMlCHAEL PACKAGING APPARATUS 8 Sheets-Sheet J INVENT OR BY erfmkp ATTORNEY Nov. 16, 1971 K. s. CARMICHAEL 3,619,910

, PACKAGING APPARATUS Original Filed July 15. 1968 8 Sheets-Sheet. a

l W L p; 706 7 F707 IN VENTOR BY wf-S-rhld ATTORNEY 3,619,919 Patented Nov. 16, 1971 hoe Int. Cl. 1365b 1/02 US. Cl. 34-216 2 Claims ABSTRACT OF THE DISCLOSURE A method and apparatus for packaging articles such as cans in an overwrap of thermoplastic polymeric material is provided wherein said apparatus comprises means for grouping a pluralty of articles to be packaged, means for enwrapping said articles with said film, means for heat-sealing overlapped edge portions of said film and enclosing said articles therewithin, means for separating said film-enwrapped grouped articles, and means for shrinking said heat-sealed film to provide a package of grouped articles characterized by a substantially wrinklefree film extending over the top, bottom, sides and portions of the ends of said grouped articles.

CROSS REFERENCE TO RELATED APPLICATION This application is a division of my copending applcation Ser. No. 744,848, filed July 15, 1968, now US. Pat. 3,572,004, issued Mar. 23, 1971.

THE INVENTION The present invention relates to a packaging apparatus and, more particularly, is directed to a novel high speed apparatus for continuously and automatically packaging groups of articles to form packaged units of increased suitability for eflicient handlng, transport, and storage. More specifically, the invention relates to a new high speed apparatus for packaging cylindrical articles such as cans to form a package consisting of six cans which is commonly referred to as a six-pack using continuously-supplied flexible heat-scalable and heat-shrinkable film or sheet of preferably transparent material.

Packaging arrangements and apparatus heretofore employed have involved bringing groups of articles and individual pre-formed package units into operative association in a noncontinuous manner, but rather intermittent in the operation of at least a number of the significant packaging steps and apparatus components. This has prevented the attainment of high packaging speeds and has resulted in fairly complex indexing mechanisms or drives. In the package resulting from the arrangement of this invention, the articles, or cans, themselves are not only supported and contained thereby, but actually form an integral and necessary part of the package providing structural unity and stability to the otherwise unrelated sleeve member. The packed articles are a necessary component of the package so that the placing and securing of the articles into proper position with respect to each other and the package components must be carried out substantially concurrently to effect formation of the package. Accordingly, it is the principal object of the present invention to provide a packaging apparatus especially adapted for continuous and high speed packaging operation.

According to the present invention there is provided an apparatus for packaging articles such as, for example, cylindrical cans in an overwrap of thermoplastic polymeric material in film form; said apparatus comprising means for providing a plurality of grouped articles to be packaged, means for providing said film, means for enwrapping said articles with said film, means for heatsealing the overlapped edges of said film and enclosing said articles to be packaged therewithin, means for separating said film-enwrapped grouped articles, and means for shrinking said heat-sealed film to provide a package of grouped articles characterized by a substantially wrinkle-free film extending over said grouped articles.

The apparatus of the present invention is automatic and of continuous operation, receives a continuous stream of regular articles of substantially uniform size, separates the articles into spaced groups, moves said groups of articles continuously along a given line of movement, forms continuously supplied flexible film around said groups as the groups move along said line of movement, continuously seals the overlapped edges of said flexible film to form a unitary sleeve assembly surrounding said groups as they move along said line of movement, continuously severs the sleeve assembly between said groups to form individual groups of articles each enclosed by a tubular sleeve member having open end portions, shrinks the open end portions of each sleeve member into engagement with the articles at the ends of the contained group of articles, and then further shinks each entire sleeve member into close engagement with all of the articles in its contained group.

The nature and advantages of the invention will be more clearly understood by the following description and the several views illustrated in the accompanying drawings wherein like reference characters refer to the same parts throughout the several views and in which:

FIGS. 1 and 1a are perspective views illustrating the general features of the apparatus of the nvention;

FIGS. 2 and 2a are diagrammatic perspective views of the drive mechanism for the apparatus of FIG. 1;

FIG. 3 is a perspective view of a preferred package produced by the apparatus of the invention;

FIG. 4 is a transverse cross-sectional view of the we shrink means of the apparatus of FIG. 1;

FIG. 5 is a side elevation view of the pre-shrink means of FIG. 4;

FIG. 6 is a perspective view showing the control features of the pre-shrink means depicted in FIG. 5;

FIG. 7 is a perspective view of the final heat-shrink means of the apparatus shown in FIG. 1;

FIG. 8 is a transverse cross-sectional view of the air supply module of the final shrink means of FIG. 1;

FIG. 9 is a longitudinal cross-sectional view along lines 2646 in FIG. 8;

FIG. 10 is a transverse cross-sectional view of the exhaust module of the final heat-shrink means of the apparatus shown in FIG. 1.

GENERAL DESCRBPTION The packaging apparatus herein disclosed in illustration of the invention is shown in FIGS. 1 and 1a and comprises in cooperative association and assembly an article feed section 100, an article grouping section 200, a film-tube forming section 300, a film supply section 400, a film-tube separating and package forming section 500, a film pre-shrink section 600 and a film final shrink section 760. The motive power for driving the apparatus of the invention is shown in FIGS. 2 and 2a and comprises drive power section 800 and drive power section 900.

The mechanical members constituting the apparatus of the present invention as shown in FIGS. 1 and 1a are supported in cooperative association by a base frame support assembly 10 composed of suitable main frame members 11 so constructed and arranged as to present a support frame resting upon a plurality of suitably disposed leg members such as 12 that are secured to said frame.

The general operation of the apparatus of the present invention is that articles 13 to be packaged such as cans, bottles, etc., are aligned in adjacent rows 14 and 15 in article feed section 100 which advances the aligned articles in the direction of arrow A. The advancing articles next enter into article grouping section 200 wherein the aligned articles are accumulated and formed into groups of any number of articles, preferably six in number. The article groups are automatically spaced from each other and advanced into the film-tube forming section 300. The travelling spaced article groups are enwrapped with a preferably transparent flexible wrapping film 18 which is fed continuously from a source or supply thereof in roll form from film supply section 400. The wrapping film is transformed in section 300 from a fiat sheet into a tubular structure that enwraps the continuously travelling line of spaced article groups, and the opposed longitudinally extending edges of the wrapping film are overlapped a suitable amount and heat-sealed together in the region of the overlap to provide a continuous tubular film that surrounds the travelling line of spaced article groups. The enwrapped or encased travelling line of spaced article groups are preferably next separated into separate article groups by advancing through film-tube separating and package forming section 500 wherein the tubular film is severed automatically at a point intermediate each adjacent spaced article group in the line thereof. The separate overwrapped article groups are next each advanced through a preshrink section 600 wherein a heated medium, preferably air, is directed against substantially only the end portions thereof whereby to selectively pre-shrink each end of the tubular wrapping film against the end articles of the article groups. The article groups are next advanced through a final shrink section 700 wherein each package is subjected to a heated medium over substantially its entire surface thereby to shrink the entire tubular wrapping film to provide a unitary package of wrapped articles characterized by a wrapping film tightly drawn over the sides, top, bottom and portions of the ends of each article group. The preferred package of six articles is shown in FIG. 3 which depicts two contiguous rows 16 and 17 each containing three containers enwrapped with a tightly-fitting heat-shrunk film 18 of flexible, transplant thermoplastic material such as, for example, polyethylene. As shown in FIG. 3, the overlapped edge portions of the film wrap is at 19 and the heat-seal in the region of the overlap is along heat seal lines 20 and 21 that are disposed in a parallel manner with respect to each other. Suitable holes 22 may be provided in the region of the film overlap between four contiguous cans to provide carrying aids adapted to accommodate fingers for lifting and carrying the package.

A more detailed description of the apparatus of the present invention is set out herebelow.

FILM PRE-SHRINK The film preshrink means is depicted at 600 in FIG. 1a. The specific features and construction of the pre-shrink means is shown in greater detail in FIGS. 4, 5 and 6. The film pre-shrink means comprises endless belt conveyor 301, endless travelling belt 601, top plenum chamber 602, bottom plenum chamber 603, blower or air circulator 604i and suitable ductwork interconnecting the plenum chambers with air circulator 604 so constructed and arranged as to provide an enclosure or tunnel 620 through which article groups 209 travel. As shown in FIGS. 1, 4 and 5, separated article groups 209 are advanced through pre-shrink means 600 on endless belt conveyor means 3011 described hereinabove. Upon entering pre-shrink means 600, the top portion of each article group 209 contacts endless traveling belt 601 consisting of endless chains 605 and 606 having pad elements 607 and rods 608 spaced therealong and connected therebetween. Endless travelling belt 601 is supported for vertical adjustment between spaced support members 609 and 610 which are in turn connected to main frame members 11 by suitable means such as posts 611 (FIG. 1) and supported thereby. Endless travelling belt 601 is adapted to be driven in timed relation to endless belt conveyor 301 by sprocket assemblies secured between support members 609 and 610 adjacent each end thereof. Pads 607 and rods 608 of endless travelling belt 601 are identical in construction and design to pads 308 and rods 309 of endless belt conveyor 301. The top portion of article groups 209 contact pad elements 607 of endless travelling belt 601 upon entering pre-shrink means 600 so that the entire top and bottom portions of article groups .209 are covered respectively by pads 607 and pads 308 as the article groups advance through the pro-shrink. The pre-shrink means 600 is adapted to direct a heated gaseous medium such as air at the end portions of wrapping film 18 which extends past the ends of separated article groups 209 thereby to shrink the Wrapping film thereat for engaging the ends of each article group 209. Preferentially shrinking the end portions of wrapping film 18 before shrinking the entire wrapping film over the article groups is preferred because the pre-shrink secures or locks the end film portions in place as shown at 612 (FIG. 4) preventing the film from sliding over either the to or bottom portions of the end articles of article groups 209 when the latter are subjected in their entirety to the final heat shrinking operation.

The heated air is directed against the wrapping film by means of blower 604 which moves heated air into and through ductwork 613 so constructed and arranged to deliver the heated air into top plenum chamber 602 and bottom plenum chamber 603. Top plenum chamber 602 is characterized by a flat top wall 614 connected to depending side walls 615 and end walls 616; one of side walls 615 is provided with an opening 617 for engaging a branch 613 of ductwork 613 for admitting heated air thereinto. The bottom portion of plenum chamber 602 is open and provided with volume flow control means 618 consisting of a plurality of adjustable vanes 619 rotatably secured between sidewalls 615 adapted to be either closed or opened any desirable amount for controlling the amount of heated air circulated therethrough. The bottom portion of plenum chamber 602 also is provided with flow direction control means consisting of a plurality of adjustable vanes 621 rotatably secured between end walls 616. As shown in FIGS. 4 and 5, the entire plenum chamber 602 assembly is supported between support members 609 and 610 intermediate the upper and lower flights 622 and 623 of endless travelling belt 601. Heated air passing through volume flow control means 618 and flow direction control vanes 621 is directed through the spaced rods 608 of endless travelling belt 601, as indicated by arrows A in FIG. 5, onto the end portions of wrapping film 18 extending beyond each end of each article group and into enclosure 620. As shown in FIG. 4, enclosure 620 is provided by endless belt conveyor 301, endless travelling belt 601 and sidewalls 624 and 625 between support frame members 11, 609 and 610.

The bottom plenum chamber 603 is identical in construction and design to plenum chamber 602 except that it is secured in position between main assembly frame members 11 intermediate the upper and lower flights of endless belt conveyor 301. Heated air enters bottom plenum chamber 603 from a branch duct 613" of ductwork 613 and flows upwardly through volume flow control means 618 and flow direction control vanes 621 and through spaced rods 309 of endless belt conveyor 301, as indicated by arrows B in FIG. 5, onto the exposed end portions of wrapping film 18 that are not covered by pad element 308.

Heated air in enclosure 620 is recirculated to blower 604 via branch duct 613' that penetrates into enclosure 620 through sidewall 625. The recirculating air is heated to any desired temperature by means of an electrical heater device 628 consisting of a plurality of heaters 629 adapted to be connected to a suitable source of electrical energy. The heater device 628 is secured in the return duct 613" of ductwork 613, as shown in FIG. 6. A unique control feature embodied in pre-shrink means 600 comprises a damper device having a damper plate 626 secured to a rod 627 rotatably mounted in ductwork 613. Rod 627 extends through a wall of ductwork 613, as indicated at 630, to provide an extension for securing actuating means 632 thereto which consists of a slotted bar 633 having an actuating pin 634 extending through the slot therein. Actuating pin 634 also extends through a spring 635 intermediate slotted bar 633, and keeper 636 and another spring 637 intermediate slotted bar 633 and keeper 638, and one end of actuating pin 634 is connected by suitable means such as chain 639 to the piston rod 640 of pneumatically operated cylinder 641. One end of spring 635 abuts directly against slotted bar 633, but the end of spring 637 adjacent bar 633 abuts against a keeper 642 secured to pin 634, and spring 635 exerts a greater force on bar 633 than spring 637 for urging damper plate 626 clockwise (FIG. 13) so that normally damper plate 626 restricts air flow through ductwork 613. Cylinder 641 is adapted to be energized by introducing a hydraulic fluid medium thereinto through a suitable valve 643 for moving the piston element therein and piston rod 640 connected thereto for exerting a pull through chain 639 on actuating pin 634, as shown in FIG. 6, thereby to cause damper plate 626 to pivot about rod 627 and rotate counterclockwise thus permitting the flow of air through ductwork 613. On the other hand, to prevent excessive build-up of heat in enclosure 645 during temporary operational shutdown of the apparatus, an electrical signal energizes normally open solenoid shut-off valve 644 which also vents the pressure in cylinder 641 thereby deenergizing cylinder 641 to release the pull on pin 634, and thus permit spring 635 to exert its force against slotted bar 633 which acts against keeper 642 to cause rod 630 and damper plate 626 to rotate clockwise, as shown in FIG. 6, for restricting the flow of air through ductwork 613.

As shown in FIG. 1, article groups 209 exit from film pre-shrink means 600 and advance to film final shrink section 700 as separate packages having the wrapping film at each end thereof heat-shrunken against and about the end articles of each article group.

FILM FINAL SHRINK Film shrink means 700 comprises support frame 701, endless conveyor 70-2 and suitable ductwork so constructed and arranged to provide a heated enclosure or tunel 712 through which article groups 209 are conveyed for heat shrinking wrapping film 18 thereby to provide the package as shown in FIG. 3.

The endless conveyor member 702 of shrink means 700 includes a plurality of spaced roller elements 704 suitably rotatably secured at each end to endless chains 705 and 706. The endless chains may be driven by an suitable arrangement as by a sprocket assembly operatively secured between support frame members 707 and 70-8 adjacent each end thereof and coupled to a prime motive source.

Support frame 701 also includes support legs 709 each connected at one end to either of support frame members 707 and 708 whereby to present endless conveyor 701 in alignment with endless conveyor 301 thereby to afford a continuing path or line of travel for article groups 209.

The ductwork 703 of film shrink means 700 is compartmented to provide in series heated air supply modules 710 and heated air exhaust modules 711, as indicated in FIG. 7. The air supply module 710 is depicted in greater detail in FIGS. 8 and 9, and air exhaust module 711 is shown in greater detail in FIG. 10.

Referring to FIGS. 7, 8 and 9, heated air supply module 710 comprises a flow duct assembly 713 and a bottom plenum chamber 714 each operatively connected to branch ducts 715 and 716, respectively, of main duct 717 that is operatively connected to air circulator or blower 718. Bottom plenum chamber 714 is identical in construction and design to plenum chamber 603 of film preshrink means 600 described hereinabove. Bottom plenum chamber 714 is secured in position between support frame members 707 and 708 intermediate the upper and lower flights of endless conveyor 702. Heated air is adapted to enter plenum chamber 714 from branch duct 716 and flow upwardly through volume flow control means 719 and flow direction control means 720 and through or between spaced roller elements 704 and onto the surface of wrapping film 18 adjacent the bottom portion of article groups 209.

Flow duct assembly 713 is of inverted U-shaped crosssection having a main flow passage 721 in communication with side flow passages 722 and 723, and comprises a top wall 724 connected to depending sidewalls 725 and 726 and a bottom wall 727 connected to perforated sidewalls 728 and 729 having a plurality of apertures 730 therein. Preforated sidewalls 728 and 729 are connected to sidewalls 725 and 726 by means of bottom walls 731 and 732, respectively, thereby to provide side flow passages 722 and 723. Bottom wall 727 of flow passage 721 is provided with suitable apertures 733 and 734 providing direct communication between flow passages 721 and 722 and between flow passages 721 and 723. Bottom wall 727 also is provided with a large aperture 735 having an upstanding flange 736 extending therearound for supporting and accommodating volume flow control means 737 and flow direction control means 738. Volume flow control means 737 and flow direction control means 738 are identical in construction and design to volume flow control means 719 and flow direction control means 720. Heated air is adapted to enter flow duct assembly 713 from branch duct 715 and be distributed therein through flow passage 721 to side flow passages 722 and 723 and through apertures 730 in the latter into enclosure 712 and against wrapping film 18 adjacent to the sides of article groups 209. The heated air in flow passage 721 also is adapted to flow through both volume flow control means 737 and flow direction control means 738 and aperture 735 onto the wrapping film 18 adjacent the top portion of article groups 209.

The heated air entering enclosure 712 from flow assembly 713 and plenum chamber 714 virtually bathes each article group 209 in a sea of hot air which results in shrinking wrapping film 18 into tight engagement with the articles of group 209 to provide the package shown in FIG. 3.

The heated air exhaust module 711 is shown in greater detail in FIG. 10 and comprises upper plenum chamber 739 and bottom plenum chamber 740 each in communication with return duct 741 which is operatively connected to blower 718. Upper plenum chamber 739 is provided with flow direction control vanes 741 suitably supported in aperture 742 therein, and the entire plenum chamber assembly is disposed immediately above article groups 209. The lower plenum chamber 740 is secured between frame supports 707 and 708 intermediate the upper and lower flights of endless conveyor 702. The lower plenum chamber 740 also is provided with flow direction control vanes 743 suitably supported in aperture 744 therein. Blower 718 is adapted to exhaust the hot air adjacent article groups 209 in enclosure 712 by way of plenum chambers 739 and 740 and return duct 741. Also, the exhaust air travelling in return duct 741 is directed over a bank of electrical heaters (not shown) suitably disposed therein and operatively connected to a source of electrical energy.

The entire final film shrink means 700- is preferably enclosed by an outer cover or shroud 703 of suitable material such as stainless steel to provide a guard especially against the heated components therein. Suitable insulation also is preferably provided on the inside of cover 703.

I claim:

1. Apparatus for packaging a plurality of articles wherein spaced groups of the articles are each enclosed in a 8 sleeve of heat shrinkable wrapping film having end porsaid belt being adapted to respectively completely cover tions extending beyond the ends of each article group, the entire top and bottom portions of each article group the improvement comprising: as it moves through said film pre-shrink means and said film pre-shrink means to first shrink substantially only spaced pads of said conveyor and said belt each defining the open end portions of each sleeve against the 5 said openings therein and therebetween. ends of each article group, said pre-shrink means including top and bottom plenum chambers, an end- References Cited less conveyor for continuously moving the spaced UNITED STATES PATENTS groups of articles through he said pie s rink means, 1,034,112 7/1912 Hopkms 34 216 X an endless belt positioned above the article groups 10 3 120 728 2/1964 S J l 53 1 4 X and adapted to be driven in timed relation to said 3239991 966 C er a 8 endless conveyor, me ns for blowing hot air into said 3,331,503 7/1967 gg gg 5 ;1g

t 1 h top a11d be torn p n m chambers and throug open 3,430,358 3/1969 Dcnker 3 222 ings in said belt and said conveyor and substantially :22 Onto the end Porno of each of sleeves 15 FREDERICK L. MATTESON, ]R., Primary Examiner final shrink means for shrinking each entire sleeve into H. B. RAMEY, Assistant Examiner engagement with the articles in each group. 2. Apparatus of claim 1 wherein said belt and said CL conveyor each include a plurality of spaced pads extending 20 53-184 therealong with a pad of said conveyor and a pad of 

